In patient care and medical research facilities, it is often necessary to dispense a small amount of blood or other fluid for purposes of testing. These fluids are often carried in various containers, many of which have an open mouth that is sealed by a rubber or other flexible stopper. Removal of the fluid from the container is often accomplished by first removing the stopper and then withdrawing, such as by use of a pipette, an amount of fluid from the container for deposit onto a slide or in some other way applied for testing. Where the container is opened, and a pipette used to withdraw the fluid, it is difficult to prevent inadvertent spattering or spillage. Thus, the healthcare worker is unnecessarily exposed to infection where infectious fluids are being tested.
One way of withdrawing fluid from these containers without removing the container cap is by use of a syringe and needle which can be inserted through the rubber cap and into the container for withdrawing of a small amount of blood or other fluid. However, the use of a syringe and needle is cumbersome and expensive and further exposes the healthcare worker to the possibility of needle pricks which can be particularly injurious where infectious fluids are being handled.
These procedures particularly increase the potential exposure of healthcare workers to the Human Immunodeficiency Virus-1 (HIV-1) which may be transmitted to the healthcare worker through infected blood. While various dispensers have been used in the past, none provide a method of easily, economically and safely dispensing a droplet of fluid from a container. The patent to Robert W. Ogle, U.S. Pat. No. 3,788,528, shows a device having a cap adapter which operates in conjunction with a specialized stopper having an existing opening therethrough. The patent to R. S. Fobes, U.S. Pat. No. 3,366,278, discloses a dispenser for liquid biologicals having an elongated tube with one end for insertion through a rubber stopper closing a container and an abutment plate for engagement with the rubber stopper for applying a pumping action to the stopper. A pumping action is caused by the engagement of the plate against the stopper.
Other devices, such as that shown in the patent to Tipton Golis, U.S. Pat. No. 4,811,866, require the use of a special dispensing nozzle which generally would require the removal of the container stopper and the application of a resilient dispensing member. A pumping action is achieved by flexing the resilient nozzle by squeezing. This device would be relatively expensive to manufacture and is not readily adaptable to all configurations of containers used. Further, prior to application of the dispenser member, the blood or other fluid within the container is exposed for possible spillage and thereby contact with the healthcare worker.